A monoclonal antibody (Mab) against a synthetic peptide, SEDYGKDL, corresponding to one conserved sequence in the chicken α-fodrin repeats reacts in immunoblotting with avian α-spectrin and α-fodrin, both mammalian spectrins and with mammalian α-fodrin. This Mab also reacts with α-actinin in both chicken and human cells. Our results confirm the previously detected structural homology between spectrins and α-actinin and implicate their common evolutionary origin.
